We’re very excited to announce that as of September 28th, 2017, Shopify API supports bulk discount code creation. With the introduction of bulk discounts, we will allow a single price rule to be associated with multiple discount codes. Therefore, an app that wishes to create multiple discount codes for a single price rule can perform additional independent API calls for each discount code they wish to create.
Furthermore, we now support the ability to create multiple discount codes in a single request via a new batch bulk discount endpoint. To learn more about creating bulk discount codes, please see the API reference here.
Please note, bulk discount code creation is only possible via the API. There is no way to create bulk discount codes via the Shopify admin.
If you have any questions or need further clarification, don't hesitate to comment in the thread below.
While you're at it, don't forget to fix the API so that when discounts are used for orders, they report correctly with the items they discounted. Without that, API orders are not reporting correct prices, which of course is a little underwhelming from an accounting perspective!
API call 101 question, but how can I create a Price Rule that only goes into effect with the application of a discount code? From there I hope I can bulk add the codes I want to use via the price rule method you listed. (Goal is to add in about 3,000 codes in batches of 100 to a single price rule)
Shopify used to have a bulk discount code app, but it was moved to a third party. https://apps.shopify.com/bulk-discounts
You can also program them yourself, using the Shopify API:
To summarize, you can use the API to batch create codes, as well as set up price rules (ie. based on a formula). Otherwise, you can use the batch discount app.